GIS Projects and Implementations


Outline

  1. Project Based GIS
  2. People Side of GIS
  3. Implementations
  4. Questions:

Project Based GIS

Omaha Election Analysis

Purpose

This project was begun back in 1987 when mayor Mike Boyle was subjected to a recall election that he lost. The Omaha World Herald wanted to know what parts of the city voted to have him recalled. At the time, neither ArcInfo nor ArcView were available at the time, so the department used the mapping software they had created. The first step was to digitize the most current voting precinct map and use it to produce the map. Because ArcView and ArcInfo, the maps produced did not have Topology and could not be used for analysis. One of the most important choices in determining the final map is the classification method. This decision was made by arbitrarily by an editor at the World Herald. He selected a division based upon 57% and 43% of the vote.

Outline Map

Whenever Omaha has an election, the production of an election map is always a time intensive project. Usually, the department would get the final map, which had been subjected to changes in precint boundaries since the last election, only a few days before the election. The digitization process usually takes around 10 hours to complete and includes over 400 precincts. Changes in the pecinct map are made on a routine basis and involve merging older precincts, in the older, eastern part of Omaha, and adding others to the newer, west part. The goal is to create a system of precincts of basically uniform population amounts.

Alternatives

Since the precinct boundaries are based upon the existing street system, it would be possible to select those street segments corresponding to precinct boundaries on an existing map to define the polygons in the maps database. Unfortunately, this process is even more time consuming than digitizing the entire map.

Data

When producting these maps, the speed with which a final product is made depends on the availability of the election data. Douglas County usually has complete results available by 11 pm the night of the election. However, Sarpy county is notoriously slow and sometimes will not have the final results tabulated for up to a week after the election.

Platte River Vegetation Encroachment

Primary Research Question

Is vegetation establishing itself along the Platte River between Grand Island and the Platte's northward turn? The Platte River is unique in that it contains thousands of sandbars which make ideal nesting habitat for waterfowl and other wildlife. These areas are maintained by a continual cleaning process where yearly flooding removes certain vegetative types, such as trees and other long second and third vegetative stage species. With the daming of the Platte River, this yearly flooding cycle has disappeared. Thus, the thesis of this project is that the dams on the Platte River have changed the ecological conditions found on the Platte River, resulting in a changing distribution of species type and amount.

Imagery

This research question requires knowledge of past conditions on the Platte River. The only source of such information is old photographs, mostly black and white, of the Platte River. Photos exist of the region from 1936,1954, 1967, and 1984. The project was one of analyzing these photographs by projecting them onto USGS Quadrangle maps using a Stereo-Transfer Scope. Basically, the photos were adjusted to match the scale of the Quadrangle map using a system of mirrors. A piece of drafting paper was placed onto the map and the outlines of vegetative types drawn. The next step was to digitize the drafting paper map. Once again, the lack of Topology created a spaghetti map with many sliver polygons. Fortunately, the sliver polygon problem was overcome by rasterizing the map. In the end, comparison of the succesive raster maps was reduced to a series of tables that described changes in raster pixels over time.

People Side of GIS

People Problems vs. Technical Problems

People problems are those associated with the individuals involved in a project while technical problems are those associated with the equipment used in the analysis. Unfortunately, the primary problems in both of the above described projects were associated with people. Communication issues, organization issues, and responsibility issues all reared there ugly heads. One can imagine that such problems would be greatly magnified in an industry GIS application.

Implementation of a GIS is a Political Process

Group dynamics often determine who is in charge of a GIS implementation. In a larger institution, information is power. "Centralized Information Systems tend to increase power of the administrators and technical experts who control them at the expense of those who lack the experience to use them effectively." In many ways, the technical experts run the show. If you have any questions, please refer to Dilbert.

Institutional Barriers

Another common problem in institutional GIS applications involves working with (or against) the existing bureaucratic structure. Because GIS is a relatively new technology that uses databases, those departments or governmental agencies in charge of collecting and analyzing that data are hesitant to let it go. Changes such as the ones GIS present often are interpreted as threats to an often archaic way of doing things. Basically, the people are afraid of losing power and, like any organism, put up a fight.

Implementations

Awareness

As with any new technology, knowledge of its usefulness can be slow to spread. As such, there are 3 different approaches to the implementation of GIS within an organization.

Top Down Design

Occurs when managers 'discover' the technology and decide that it needs to be implemented. In many cases, the individuals deciding that GIS is a necessary tool are not technically competent in its effective application. They have the resources and can convince others of the need for GIS but must have help in implementing the actual hardware and software.

Bottom Up Design

This occurs when the employees involved in working on projects see GIS and its usefulness. They begin pushing the higher ups for resources to implement GIS applications. Most of the time these individuals run into cost justification problems. They must show that the new approach will save time and money. However, justification for GIS implementation is much easier when lives hang in the balance. For example, 911 service was improved with a GIS by justifying the money required with the potential lives saved.

Third Party Approach

Involves consultants who come into an organization and determine that a company may benefit from GIS. Convergent Group

System Requirements

These are the needs for a specific GIS implementation.

Evaluation of Alternative Systems

This stage requires careful consideration of various GIS software packages and their necessary hardware components. User needs and interface are of primary consideration. ESRI Smallworld GIS

System Justification and Development

This is a step by step implementation plan and involves a cost/benefit analysis to justify its implementation.

Operational System

Oftentimes, this is the most difficult portion of an implementation because it involves deciding who gets what data, who can modify which database, and who is responsible for what.

Major Costs

Which of the above costs is the highest? Of the above, training, salaries, and other people costs contribute by far the most to any GIS implementation.

Questions


Submitted by Jess Behrens on 4-13-98.